N-trihaloacetyl aspartic acid dipeptide ester sweetening agents

ABSTRACT

DISCLOSED HEREIN ARE DERIVATES OF L-ASPARTIC ACID WHICH HAVE UTILITY AS ARTIFICAL SWEETENER AGENTS. ALSO DISCLOSED IS A METHOD FOR PRODUCING SUCH DERIVATIVES.

United States Patent @flice Patented June 4, 1974 us. (:1. 260-1125 3Claims ABSTRACT OF THE DISCLOSURE Disclosed herein are derivates ofL-aspartic acid which have utility as artifical sweetener agents. Alsodisclosed is a method for producing such derivatives.

This is a division of application Ser. No. 81,533, filed Oct. 16, 1970now U.S. Patent 3,725,453.

BACKGROUND OF THE INVENTION This invention relates to new and usefulL-aspartic acid derivatives and non-toxic pharmaceutically acceptablesalts thereof. These compounds have utility as artificial sweeteningagents.

Synthetic sweetening agents have an established func tion in loweringthe intake of sugar by persons who, of necessity, must do so, i.e.diabetics. Further, the widespread occurrence of obesity as a medicalproblem has created a demand for sugar substitutes which may be used inproviding diets of normal taste and lowered caloric value. However, veryfew substances available exhibit a sweet taste and are also acceptableto the consumer. Because of recent adverse publicity the cyclamates havediminished in importance as artificial sweeteners and the largestartifical sweetener in public use today is saccharin. However, saccharinhas the disadvantage of creating a bitter aftertaste following use insubstantial portions of the population. The attempt to find a newartificial sweetening agent, easily manufactured without the drawbacksof saccharin or the cyclamates has culminated in the present invention.

Although no valid theory exists for predicting sweetness of chemicalcompounds, Moncrieff (Moncriefl, R. W., The Chemical Senses, L. HillLtd., London, 1951) has pro posed some generalizations for sweeteners asfollows: (1) polyhydroxy and polyhalogenated aliphatic compounds aregenerally sweet; (2) a-aminoacids are usually sweet, but the 3 or 6aminoacids are not, and the closer together the amino group and thecarboxy group, the greater the sweetness; (3) on ascending a homologusseries, taste changes from sweet to bitter, and taste and watersolubility disappear simultaneously; (4) alkylation of an amino or amidogroup often gives a sweet tasting compound; (5) one nitro group in amolecule often gives a sweet taste; (6) some aldehydes are sweet,ketones are never sweet.

Over the years since 1879, the date of the discovery of saccharin, alimited number of compounds have been discovered to have sweetness. Veryfew of these sweet compounds have been found to be non-toxic, andacceptable to the food and drug industry. These compounds are ofinterest since they reflect the diversity of chemical structures havingsweetness and in fact detract from the attempts to correlate sweetnesswith chemical configuration. For reviews of sweet chemical compounds,see Bottle, R. T., Manufacturing Chemist, 35, 60 (1964); Ver-kade, P.E., Farmaco (Pavia) Ed. Sci., 23, 248 (1968).

1969, Mazur et al. (Mazur, R. H.; Schlatter, J. M.; I

and Goldkamp, A. 'H.; Journ. Am. Chem. Soc., 91, 2684,

1969), reported the pronounced sucrose-like taste ofL-aspartyl-L-phenylalanine methyl ester (I). The requirement of absoluteL-configuration was necessary for sweetness. Mazur et a1. extended theirstudies to include compounds (peptide esters) of Formula (II), wherein Xwas other amino acids of the L-configuration, Asp. is aspartyl. Thenomenclature and abbreviations are according to IUPAC-IUP Commission inBiochemical Nomenclature, Biochim. Biophys. Acta, 121, l (1966). When Xis methionine or tyrosine the carboxyl group is 8 and equivalentsweetness was found.

COzH

Asp-X-OCH:

This activity was specific since substitution with other amino acidsresulted in the loss of sweetness. If the aspartyl group was replaced byother amino acids (Y) the products, Formula (III) Phe-OCH isphenylalanine methyl ester, were bitter to the taste Y--PheOCI-I Also,,B-carboxy peptides, Formula (IV) were bitter to the taste.

Pile-OC Asp-C0211 (IV) Mazur et a1. concludes that the aspartic acidamino group had to be unsubstituted and an ester on the C-terminalcarboxyl was required for sweetness. They further state that Ifretention of sweetness is desired, changes in the aspartic acid partcannot be made, but there is room for substantial manipulation of thephenylalanine portion. As if to fulfill the prior art unpredictabilityof sweetness in chemical compounds and to further substantiate thepotential problems in predicting chemical structure and sweetness,applicants have made their unobvious and unexpected discovery herein setforth.

SUMMARY The present invention relates to novel compounds of theL-aspartic acid configuration having the formula:

(V) wherein R is hydrogen, trichloroacetyl or trifiuoroacetyl; and R isphenyl, p-chlorophenyl, p-fiuorophenyl, p-bromophenyl, p-cyanophenyl,L-l-(lower)alkoxycarbonyl-2- phenethyl, L-1-(lower)alkoxycarbonyl 2 (phydroxyphenyl)ethyl or L-l-(lower)alkoxycarbonyl-3-(methylthio)propyl,with the proviso that when Ris hydrogen, R is phenyl, p-chlorophenyl,p-fluorophenyl, 'p-bromophenyl or p-cyanophenyl; and the non-toxicpharmaceutically acceptable salts thereof. Included within the scope ofthe compounds of Formula (V) are compounds having the formula:

wherein R is as set forth previously; and R is trichloromethyl ortrifluoromethyl; and the non-toxic pharmaceutically acceptable saltsthereof. Of particular interest are the compounds of Formula (V I)identified as:

N-(L-a-carboxyphenethyl)-3-(2,2,2-trifluoroacetamido)- L-succinamicacid, N-methyl ester; N- (L-a-carboxyphenethyl) -3- 2,2,2-trifluoroacetamido) L-succinamic acid, N-meth'yl ester, dicyclohexylamine salt;L-3-(2,2,2-trifluoroacetamido)succinanilic acid; L-4'-chloro-3-(2,2,2-trifiuoroacetamido succinanilic acid;L-4'-chloro-3-(2,2,2-trifluoroacetamido)succinanilic acid,

dicyclohexylamine salt;4-fiuoro-3-(2,2,2-trifluoroacetamido)-L-succinanilic acid;4'-fluoro-3-(2,2,2-trifiuoroacetamido)-L-succinanilic acid,dicyclohexylamine salt;L4-bromo-3-(2,2,2-trifluoroacetamido)succinanilic acid;L-4'-cyano-3-(2,2,2-trifluoroacetamido)succinanilic acid;L-4'-cyano-3-(2,2,2-trichloroacetarnido)succinanilic acid.

Also included Within the scope of the compounds of Formula (VI) arecompounds having the Formula:

(VII) wherein R is hydrogen, chloro, fluoro, bromo or cyano; and thenon-toxic pharmaceutically acceptable salts thereof. Of courseparticular interest are the compounds of Formula (VII) identified as:

L-3-amino-4'-chlorosuccinanilic acid; L-3-amino-4-cyanosuccinanilicacid.

When used herein and in the appended claims, the term (lower)al'koxycontemplates hydrocarbonoxy radicals, straight and branched chain,containing from about 1 to about 6 carbon atoms, and includes methoxy,ethoxy, n-propoxy, i-propox'y, n-butoxy, t-butoxy, n-pentoxy, n-hexoxy,Z-methylpentoxy, and the like. Non-toxic pharmaceutically acceptablesalts include, for example, sodium, potassium, calcium, ammonium,cyclohexylamine, N,N-dibenzylethylenediamine salts, and the like. Alltemperatures expressed herein are in degrees Centigrade, unlessotherwise indicated.

The principal object of this invention is to provide novel L-asparticacid derivatives and non-toxic pharmaceutically acceptable salts thereofwhich are useful as sugar substitutes or synthetic sweeteners. Verysurprisingly, it has been found that the compounds of the presentinvention, Formula (V), exhibit a sweet taste without any accompanyingbitter aftertaste and are non-toxic.

In the pharmacological evaluation of the compounds of this invention(Formula V), the toxicity was measured as follows:

The compound to be tested is administered intraperitoneall'y and/ororally to three mice (14 to 24 grams) at each of the following doses:400, 127, 40 and 12.7 mg./kg. The animals are watched for a minimum oftwo hours, during which time signs of general stimulation (i.e.increased spontaneous motor activity, hyperactivity on tactilestimulation, twitching), general depression (i.e. decreased spontaneousmotor activity, decreased respiration) and autonomic activity (i.e.miosis, mydriasis, diarrhea) are noted. The animals are tested forchanges in reflexes (i.e. flexor, extensor) and are rated by use of apole climb and inclined screen for the presence of sedation-ataxia. TheEddy Hot-Plate Method [Nathan B. Eddy and Dorothy Leirnbach, J.Pharmacol. Exper. Therap. -107, 385 (1953)] is used to test foranalgesia. The experiment is terminated by subjecting each animal to amaximal electroshock to test for anticonvulsant activity. The compoundsof the present inven- 4 tion, when tested by the above procedure,demonstrated no oral toxicity at a level that prevented the followingisosweetness test.

The quantitative evaluation of sweetness was based on comparing thecompounds of the present invention (Formula V) with a standard solutionof sucrose (0.06 M). The test is for isoweetness and is based on onedescribed by R. H. Mazur et al., Structure-Taste Relationships of SenseDipeptides, Journ. Am. Chem. $00., 91:10, May 7, 1969. The testprocedure is as follows: Test compounds were dissolved in water andadjusted to pH 7 with dilute sodium hydroxide. A cotton swab stick wassoaked in the test solution and the compound was sucked off the swab andtasted by adult volunteers. Successive dilutions were made untilapproximately the same quantitative sweet taste of the test compound andstandard sucrose solution (0.06 M) was obtained. Relative sweetness wascalculated by dividing the molarity of the standard sucrose soltuion(0.06 M) by the molarity of the isosweet test solution. The compounds ofthis invention were surprisingly more sweet than sucrose by the aboveprocedure. For example, L-4'-cyano 3 (2,2,2trifluoroacetamido)succinanilic acid andL-4'-cyano-3-(2,2,2-trichloroacetamido)succinanilic acid, calcium saltwere each about 3000 times as sweet as sucrose and L-4'-chloro-3-(2,2,2-trifluoroacetamido)succinanilic acid was about times as sweet assucrose.

The chemical structure necessary to provide a sweet taste is relativelyspecific. Table 1, following, sets forth the presence or absence ofsweetness in a series of related compounds. The presence of sweetness isindicated by a plus whereas the absence of sweetness is indicated by aminus Table 1 demonstrates the relatively narrow scope of the presentinvention in that structurally similar compounds do not possess a sweettaste.

TABLE 1 Sweet -CHCO2M0 FaC- -CH2(CHz)r-CH:

FaC-

SO2NH2 FaC FaC

FaC

TABLE 1Continued X Y Sweet FaC- U1 QR ocmcn.

FzC- q -CH2CH2OH EC- F I IiQ-'.

F:C- (1H3 I -QI1-(CH2)4CH:

FaC-

F;{C---.;.. COzH ClzC- Same as above H- An wherever a sweet tastewithout caloric value is indicated.

This would include comestibles such as food or medicines intended forhuman or' animal consumption. Such items as soda, ice cream, coffee, teaand chewable medications would particularly lend themselves for use withcompounds of the present invention. For example, when several drops of a100 mg./cc. solution of L-4-cyano-3-(2,2,2-trifiuoroacetamido')succinanilic acid are added to iced tea orhot coffee, a sweet taste not unlike when sucrose sweetened is obtained.For example, when 2 mg. of L-4-cyano-3 (2,2,2trifluoroacetamido)succinanilic acid is added to 250 cc. (one cup) ofhot coffee with cream, the taste is indistinguishable from that of 5 g.of table sugar. Additionally, the compounds of this invention may becombined with other synthetic sweetening agents or with sugars toprovide sweetening compositions.

The compounds of the present invention of the L- aspartic acidconfiguration having the formula:

I E) CHz( JOH IR--NH- ]El-(fi-NHR 0 (VIII) wherein R and R are aspreviously set forth, are provided by a process which comprisescontacting an L- aspartic anhydride of the formula:

CHr- C wherein R is as previously set forth, with a compound of theformula:

wherein R is as previously set forth until said compound of :Formula(VIII) is provided. The contacting may take place at any temperatureranging from ambient room temperature (about 25 C.) up to the refluxtemperature of the reactants. However, a temperature should be used thatdoes not adversely affect the reactants. It has been found that thereaction proceeds favorably at room temperature when allowed to remainin contact from overnight up to about a week. It is also advisable touse a reaction inert organic solvent to dissolve the reactants. Thesereaction inert organic solvents would be those which dissolve thereactants but do not adversely affect the reaction or the reactants andinclude solvents such as tetrahydrofuran, dimethylsulfoxide,dimethylformamide, and so forth. The compound of Formula (VIII) isrecovered by routine procedures, i.e. removing the solvent (as by vacuumdistillation), washing with an acid (hydrochloric acid) andrecrystallizing from an appropriate solvent (acetonitrile, n-butanol,methanol isopropyl ether). If desired, salts of the compounds areprovided by routine procedures.

The starting materials of Formula (X) are Well known or provided byroutine techniques readily available to those skilled in the art. Thestarting materials of [Formula (IX) are also known and may be providedby reacting aspartic acid and the appropriate tri(halo)acetic anhydridein an ice bath. The compounds of Formula (V), wherein R is hydrogen, areprovided from the equivalent compounds of Formula (VIII) by cleaving thetri(halo) acetyl in a base such as ammonium hydroxide with heating ifnecessary. The resulting 3-amino compounds are recovered by routineprocedures.

The following examples are given by way of illustration and are not tobe construed as limitations of this invention, many variations of whichare possible without departing from the scope and spirit thereof.

EXAMPLE 1 N-trifluoroacetyl-L-aspartic acid anhydride L-asparatic acid,212.8 g. (1.6 mole) is placed in a 2 liter round bottom flask fittedwith a stirring motor, dropping funnel, and water condenser. Flask iscooled in a Dry Ice-acetone bath and trifluoroacetic anhydride, 840 g.(4 mole), is added with continuous stirring of the mixture over a periodof 45 minutes. Bath is removed and the contents of flask are permittedto warm up. Reaction becomes vigorous at 14 C. with the evolution ofheat.

After reaction has subsided,.the contents of the flask are refluxed fortwo hours and then cooled to room tempera- L-3- (2,2,Z-trifluoroacetamido) succinanilic acid Dissolve N-trifluoroacetylaspartic acid anhydride, 10.5 g. (0.05 mole) and aniline, 4.6 g. (0.05mole) in 40 ml. of dry tetrahydrofuran. After standing overnight at roomtemperature, the solvent is removed and the residue triturated with 200ml. of 2 N HCl. Product is collected and crystallized fromacetone-water. Yield: 7.3 g. (48%); M.P. 197198 C.

Analysis.-Ca1cd. for C12H11NZO4F3: C, 47.38; H, N, 9.20. Found: C,47.22; H, 3.86, N, 9.17.

EXAMPLE HI 4'-brorno-3-(2,2,2-trifiuoroacetamido)-L-succinanilic acidDissolve N-trifluoroacetyl-L-aspartic acid anhydride, 21.1 g. (0.1 mole)and p-bromoaniline, 17.2 g. (0.1 mole) in 300 ml. of dry tetrahydrofuran. After four days at room temperature, the solvent is removed,and the residue is crystallized from 75 ml. of hot acetonitrile. Yield:18 g. (47% M.P. 200-202 C.

Analysis.Calcd. for C H N O F BL: C, 37.72; H, 2.63; N, 7.31. Found: C,37.31; H, 2.68; N, 7.29.

EXAMPLE IV L-4'-chloro-3-'(2,2,2-trifluoroacetamido)succinanilic acid,dicyclohexylamine salt Dissolve 10.5 g. (0.05 mole) ofN-trirfluoroacetyl-L- aspartic acid anhydride and 6.4 g. (0.05 mole) ofpchloroaniline in 100 ml. of dry tetrahydrofuran. After standingovernight at room temperature, the solvent is removed. The residue isdissolved in methanol, reacted with 9 g. (0.05 mole) ofdicyclohexylamine, and the product crystallized from methanolisopropylether. Yield: 9.7 g. (38%); M.P. 217 C. with decomposition.

Analysis.-Calcd. for C ,H N O CIF C, 55.54; H, 6.39; N, 8.08. Found: C,55.49; H, 6.13; N, 7.99.

EXAMPLE V 4-fluoro-3- (2,2,2-trifiuoroacetamido) -L-'succinanilic acid,dicyclohexylamine salt Dissolve N-trifluoroacetyl-L-aspartic acidanhydride, 10.5 g. (0.05 mole) and p-fluoroaniline, 5.5 g. (0.05 mole)in 100 ml. of dry tetrahydrofuran. After two days, the solvent isremoved and the oily residue is triturated with ether untilcrystallization occurs. The product is washed. with 200 m1. of 2 N HCl,collected, and dissolved in acetone. After the addition of 9 ml. ofdicyclohexylamine, water is added until crystallization is initiated.After standing overnight at 4 C., the product is collected andrecrystallized from methanol-isopropyl ether. Yield: 8.5 g. (34.2%);M.P. 218 C. with decomposition.

Analysis.Calcd. for C24H33N3O'4F4I C, H, N, 8.34. Found: C, 57.20; H,6.67; N, 8.64.

EXAMPLE VI Dissolve 4.95 g. 0.023 mole) of L-phenylalanine methyl esterHCl in 10 ml. methanol and add 2.32 g. (0.023 mole) of triethylamine toneutralize the hydrochloric acid. Add 200 ml. of ether and cool themixture tCY IS? C. After one hour, the precipitated triethylaminehydrochloride is collected and discardedflIhe filtrate is evapporated toremove solvents" and the residue is dissolved in 50 ml. of drytetrahydrofuran. After the addition of 4.85 g. (0.023 mole) of Ntrifiuoroacetyl-L-asparatic acid anhydride in 25 ml. of dryTHF thesolution is set aside and allowed to stand at room temperature for sixdays. The solvent is removed and the residue taken up in methanol andreacted with 4.1 g. (0.023 mole) of dicyclohexylamine with ether. Thecrystallineproduct is collected and recrystallized frommethanol-isopropyl ether. Yield: 6.9 g. (52.7%); M.P. 152-154 C. 7 h ,1

Analysis.--Calcd. for C H N 0 F C, 58.83; H, 7.05; N, 7.35. Found: C,58.83; H, 7.02; N, 7.42.

Similarly, using the appropriate methionine (lower) alkyl ester ortyrosine (lower)alkyl ester starting material, the following compoundsare provided;

N- [L-u-carb oxy-3- (methylthio )propyl] -3-2,2,2-trichloroacetamido)-L-succinamic acid, N-methyl ester, calciumsalt; r Y'N-[L-a-carboxy-3-(methylthio)propyl]-3-(2,2,2-trifiuoroacetamido)'-L-succinamicacid, N-butyl ester, dicyclo i hexylamine salt; 7

N- [L-a-carboxy (p-hydroxyphenyl) ethyl] -3(2,2,2-trifiuoroacetamido)-L-succinamic acid, N-methyl ester,dicyclohexylamine salt;

N-[L-u-carboxy(p-hydroxyphenyl)ethyl]-3-(2,2,2-trichloroacetamido)-L-succinamicacid, N-propyl ester, calcium salt. I

EXAMPLE VII N-(L-a-carboxyphenethyl) 3-(2,2,2-trifluoroacetamido)-L-succinamic acid, 5 N-methyl ester DissolveN-trifiuoroacetyl-L-aspartic acid anhydride, 10.5 g. (0.05 mole) andL-phenylalanine methyl ester, 10.8 g. (0.05 mole) in 200 ml. of drytetrahydrofuran. Let stand two days atToom temperature, remove .thesolvent, and crystallize the residue from hot acetonitrile. Yield: 10.5g. (54%); M.P. .150-152 C.

Analysis.Calcd. for C H N O F C, 49.23; H, 4.38; N, 7.17. Found: C,49.30; H, 4.46; N, 7.52. 7

In a. similar manner, using the appropriate starting materials, thefollowing compounds are provided:N-(L-a-carboxyphenethyl)-3-(2,2,2-trifluoroacetamido)- 'Lsuccinamicacid, N-ethyl ester; andN-(Ira-carboxyphenethyl)-3-(2,2,2-trifiuoroacetamido)- L-succinamicacid, N-propylester.

trifiuoroacetan'iido)succinanilic acid'in 400 ml. of 1 N NH OH and stirreaction for one hour. Water is removed in :a roto evaporator toapproximately 150, ml.

pH .is adjusted to..,7] withtrifluoroacetic acidandthe volutne reducedto mLfCrystals form afte'r' standing with decomposition.

Anulysis. Calcd. f f.,,..H;;s,c1o;-j 49150; n, 4.56; N, 11.54. Found: c,49.54; 11, 4.68; 1 1,171.5

L 4' cyano-3 (2,2,2-trifluoroacetamido)succinariilic acid, 9 g. (0.027mole), is dissolvedinlOO ml. of .halfconcentrated ammonium hydroxide andstirred for fifty minutes. The solution is subsequently rapidly heateduntil 85 C. is reached and the flask is removed from the source of heat.Water is removed by means of a rote-evaporator until a solid residue isobtained. The residue is dissolved in methanol and again taken todryness. Finally, the residue is refluxed in 70 ml. of n-butanol and themixture is set aside at room temperature and let stand overnight. Theproduct is collected and dried in vacuo at 40 C. for three hours. Yield:6 g. (92.5%); M.P. 215 C. with decomposition.

Analysis.Calcd. for CHI-111N303: C, H, N, 18.01. Found: C, 56.45; H,4.78; N, 18.17.

EXAMPLE X L-4-cyano-3-(2,2,2-trichloroacetamido)succinanilic acid,calcium salt Combine 13 g. (0.05 mole) of trichloroacetyl-L- asparticacid anhydride and 5.9 g. (0.05 mole) of 4- cyano-analine in 100 ml. ofdry tetrahydrofuran and let stand five days at room temperature. Solventis removed and replaced with 100 ml. methanol. Calcium acetate (0.025mole) dissolved in 50 ml. water is added. S01ution is completed by theslow addition of water. After the removal of methanol and water in arote-evaporator, the dry residue is crystallized and recrystallized fromnbutanol. Yield: 7 g. (35.2%); M.P. 226 C. with decomposition.

AnalysiS.-CalCd. fOr cgsH gNsogclficai C, H, 2.28; N, 10.56. Found: C,39.31; H, 2.52; N, 9.73.

EXAMPLE XI L-4'-cyan0-3-(2,2,2-trifiuoroacetamido)succinanilic acidCombine 21.1 g. (0.1 mole) of trifluoroacetyl-L-aspartic acid anhydrideand 11.8 g. (0.1 mole) of 4-cyanoanaline in 200 ml. of drytetrahydrofuran and let stand five days at room temperature. Solvent isremoved and residue is crystallized from acetonitrile. Yield: 10.5 g.(32%); M.P. 187-189 C.

Analysis.Calcd. for C H N O F C, 47.43; H, 3.06; N, 12.76. Found: C,46.80; H, 3.53; N, 12.87.

10 What is claimed: 1. A compound of the L-aspartic acid configurationhaving the formula:

wherein R is L-l-(lower)alkoxycarbony1-2-phenethyl, L- 1-( lower)alkoxycarbonyl-Z- p-hydroxyphenyl) ethyl or L 1-(lower)alkoxycarbonyl-3-(methylthio)propyl, and R is trichloromethyl ortrifluoromethyl; and the non-toxic pharmaceutically acceptable saltsthereof.

2. A compound, as set forth in claim 1, which is: N-(L-a-carbomethoxyphenethyl) 3 (2,2,2-trifluoroacetamido)L-succinamicacid.

3. A compound, as set forth in claim 1, which is:N-(L-a-carbomethoxyphenethyl) 3 (2,2,2 trifluoroacetamido)-L-succinamicacid, dicyclohexylamine salt.

References Cited UNITED STATES PATENTS 3,714,139 1/1973 Schlatter260112.5 3,695,898 10/1972 Hill et a1. 260112.5 3,678,026 7/1972Ariyoshi et al. 26'0'--112.5 3,492,131 1/ 1970 Schlatter 260-11253,475,403 10/1969 Mazur et a1 260112.5

OTHER REFERENCES Maznr et al., J. Am. Chem. Soc., 91, 2684 (1969).

Wolman, The Chemistry of the Amino Group, S. Patai, ed., Interscience,NY. (1968), p. 672.

Weygard et al., Ann. 658, 128-50 (1962) Chem. Abstr. 58:7941b.

Liwschitz et al., Bull. Res. Council Israel, See. A, 10, 107-10 (1961);Chem. Abstr. 58:3507f.

LEWIS GOTTS, Primary Examiner R. J. SUYAT, Assistant Examiner US. Cl.X.R. 99141 A

